A Contrarian Take on a Tech Stock

Bad news is often good news for a stock. This contrarian logic animates the upper echelons of the investing world, and is driving discussions of Cognizant Technology Solutions following Monday's sharp decline.

Citigroup is telling clients to buy shares of the information-technology provider, arguing that the company's revenue could increase by 20% annually—which coincidentally is how much the stock fell on Monday after reporting...